Drywall finishing tool adapter

Claim 2

An adapter for attachment to a mastic applicator and finishing tool flat box for controlling the application of a layer of mastic on wallboard adjacent a corner bead, the adapter comprising: (a) a guide plate and an outside corner guide slidably mounted on the guide plate, and means for fixedly fastening the guide plate to a corner end of a sidewall of the flat box adjacent an end of a bottom wall of the flat box having an outlet through which mastic is dispensed; and (b) the outside corner guide being slidably retained on the guide plate for movement on the guide plate between a retracted position and an extended position by overlying portions of the means for fastening the guide plate to the corner end of a sidewall of the flat box, the outside corner guide having a first end portion and a second end portion, the outside corner guide first end portion in retracted position of the corner guide on the guide plate inoperatively overlies said guide plate, and the outside corner guide first end portion in extended position of the corner guide on the guide plate being positionable to overlie the outside of a corner bead, whereby the movement of a flat box along the corner bead can be guided to limit the application of the mastic to the wallboard to filling the corner bead, the guide plate having a lateral depending end flange portion positioned to provide a friction wear shoe beneath the corner guide.

Claim 3

An adapter according to claim 1, in which: the second end portion of the corner guide has an upstanding flange that can be gripped to move the corner guide in retracted and extended directions.

Claim 4

An adapter according to claim 1, in which: the guide plate has longitudinally extending channels along each side thereof in which the corner guide is slidably received for retraction and extension movements.

Claim 5

An adapter according to claim 3, in which: the means for fastening the guide plate to a flat box side wall comprises retainer screws, and the corner guide has at least one longitudinal slot paralleling the guide plate channels receiving one of the guide plate retainer screws for holding the corner guide in the channels of the guide plate.

Claim 6

An adapter according to claim 4, in which: the length of the slot in the corner guide controls the retracted and extended positions of the corner guide.

Claim 7

In combination: A mastic applicator and finishing tool flat box for controlling the application of a layer of mastic to wallboard adjacent outside corner beads, the flat box having end walls and a bottom wall having an elongated mastic outlet extending across its width, and adapters attached to the applicator end walls for controlling the application of mastic on a wallboard surface adjacent a corner bead, comprising: a pair of elongated guide plates, means for fastening one of the pair of guide plates on each end wall adjacent the ends of the bottom wall mastic outlet, outside corner guides slidably mounted on each guide plate for selective movement between a retracted and an extended position, the corner guides each having a first end portion and a second end portion, each corner guide first end portion having a terminal edge portion which in retracted position of the corner guide lies above the bottom wall of the flat box allowing the latter to be used for normal application of mastic on flat wallboard surfaces, and either corner guide being selectively extendible below the bottom wall to enable its first end portion to straddle a selected outside corner bead to be filled with mastic as the corner guide guides the movement of the flat box along the straddled corner bead, each guide plate having a lateral end flange portion positioned to underlie a lower end wall edge and an adjacent portion of the bottom wall of the flat box, wherein the end flange portions provide friction wear shoes between the bottom of the flat box end walls and the wallborad surface being reversed by the flat box.

Claim 8

In combination: A mastic applicator and finishing tool flat box for controlling the application of a layer of mastic to wallboard adjacent outside corner beads, the flat box having end walls and a bottom wall having an elongated mastic outlet extending across its width, and adapters attached to the applicator end walls for controlling the application of mastic on a wallboard surface adjacent a corner bead, comprising: a pair of elongated guide plates, means for fastening one of the pair of guide plates on each end wall adjacent the ends of the bottom wall mastic outlet, outside corner guides slidably mounted on each guide plate for selective movement between a retracted and an extended position, the corner guides each having a first end portion and a second end portion, each corner guide first end portion having a terminal edge portion which in retracted position of the corner guide lies above the bottom wall of the flat box allowing the latter to be used for normal application of mastic on flat wallboard surfaces, and either corner guide being selectively extendible below the bottom wall to enable its first end portion to straddle a selected outside corner bead to be filled with mastic as the corner guide guides the movement of the flat box along the straddled corner bead, each guide plate having a lateral end flange portion positioned to underlie a lower end wall edge and an adjacent portion of the bottom wall of the flat box, wherein the end flange portions provide friction wear shoes between the bottom of the flat box end walls and the wallborad surface being reversed by the flat box.

Claim 9

The combination flat box and adapters according to claim 8, in which: the guide plates have longitudinally extending side channels in which the corner guides are slidable for retraction and extension movements, and the means for fastening the guide plates to the flat box end walls are retainer screws, the corner guides have longitudinally extending slots receiving the retainer screws, and the length of the slots control the retracted and extended position of the corner guides.

Claim 10

The combination flat box and adapters according to claim 7, in which: The second end portions of the corner guides have upstanding finger grippable portions for moving the corner guides in retracted or extended directions.